4,930 research outputs found
Hydrogel-based logic circuits for planar microfluidics and lab-on-a-chip automation
The transport of vital nutrient supply in fluids as well as the exchange of specific chemical signals from cell to cell has been optimized over billion years of natural evolution. This model from nature is a driving factor in the field of microfluidics, which investigates the manipulation of the smallest amounts of fluid with the aim of applying these effects in fluidic microsystems for technical solutions. Currently, microfluidic systems are receiving attention, especially in diagnostics, \textit{e.g.} as SARS-CoV-2 antigen tests, or in the field of high-throughput analysis, \textit{e.g.} for cancer research.
Either simple-to-use or large-scale integrated microfluidic systems that perform biological and chemical laboratory investigations on a so called Lab-on-a-Chip (LoC) provide fast analysis, high functionality, outstanding reproducibility at low cost per sample, and small demand of reagents due to system miniaturization. Despite the great progress of different LoC technology platforms in the last 30 years, there is still a lack of standardized microfluidic components, as well as a high-performance, fully integrated on-chip automation. Quite promising for the microfluidic system design is the similarity of the Kirchhoff's laws from electronics to predict pressure and flow rate in microchannel structures. One specific LoC platform technology approach controls fluids by active polymers which respond to specific physical and chemical signals in the fluid. Analogue to (micro-)electronics, these active polymer materials can be realized by various photolithographic and micro patterning methods to generate functional elements at high scalability.
The so called chemofluidic circuits have a high-functional potential and provide ârealâ on-chip automation, but are complex in system design. In this work, an advanced circuit concept for the planar microfluidic chip architecture, originating from the early era of the semiconductor-based resistor-transistor-logic (RTL) will be presented. Beginning with the state of the art of microfluidic technologies, materials, and methods of this work will be further described. Then the preferred fabrication technology is evaluated and various microfluidic components are discussed in function and design. The most important component to be characterized is the hydrogel-based chemical volume phase transition transistor (CVPT) which is the key to approach microfluidic logic gate operations. This circuit concept (CVPT-RTL) is robust and simple in design, feasible with common materials and manufacturing techniques. Finally, application scenarios for the CVPT-RTL concept are presented and further development recommendations are proposed.:1 The transistor: invention of the 20th century
2 Introduction to fluidic microsystems and the theoretical basics
2.1 Fluidic systems at the microscale
2.2 Overview of microfluidic chip fabrication
2.2.1 Common substrate materials for fluidic microsystems
2.2.2 Structuring polymer substrates for microfluidics
2.2.3 Polymer chip bonding technologies
2.3 Fundamentals and microfluidic transport processes
2.3.1 Fluid dynamics in miniaturized systems
2.3.2 Hagen-Poiseuille law: the fluidic resistance
2.3.3 Electronic and microfluidic circuit model analogy
2.3.4 Limits of the electro-fluidic analogy
2.4 Active components for microfluidic control
2.4.1 Fluid transport by integrated micropumps
2.4.2 Controlling fluids by on-chip microvalves
2.4.3 Hydrogel-based microvalve archetypes
2.5 LoC technologies: lost in translation?
2.6 Microfluidic platforms providing logic operations
2.6.1 Hybrids: MEMS-based logic concepts
2.6.2 Intrinsic logic operators for microfluidic circuits
2.7 Research objective: microfluidic hydrogel-based logic circuits
3 Stimuli-responsive polymers for microfluidics
3.1 Introduction to hydrogels
3.1.1 Application variety of hydrogels
3.1.2 Hydrogel microstructuring methods
3.2 Theory: stimuli-responsive hydrogels
3.3 PNIPAAm: a multi-responsive hydrogel
4 Design, production and characterization methods of hydrogel-based microfluidic
systems
4.1 The semi-automated computer aided design approach for microfluidic systems
4.2 The applied design process
4.3 Fabrication of microfluidic chips
4.3.1 Photoresist master fabrication
4.3.2 Soft lithography for PDMS chip production
4.3.3 Assembling PDMS chips by plasma bonding
4.4 Integration of functional hydrogels in microfluidic chips
4.4.1 Preparation of a monomer solution for hydrogel synthesis
4.4.2 Integration methods
4.5 Effects on hydrogel photopolymerization and the role of integration method
4.5.1 Photopolymerization from monomer solutions: managing the diffusion of free
radicals
4.5.2 Hydrogel adhesion and UV light intensity distribution in the polymerization
chamber
4.5.3 Hydrogel shrinkage behavior of different adhesion types
4.6 Comparison of the integration methods
4.7 Characterization setups for hydrogel actuators and microfluidic measurements . 71
4.7.1 Optical characterization method to describe swelling behavior
4.7.2 Setup of a microfluidic test stand
4.8 Conclusion: design, production and characterization methods
5 VLSI technology for hydrogel-based microfluidics
5.1 Overview of photolithography methods
5.2 Standard UV photolithography system for microfluidic structures
5.3 Self-made UV lithography system suitable for the mVLSI
5.3.1 Lithography setup for the DFR and SU-8 master exposure
5.3.2 Comparison of mask-based UV induced crosslinking for DFR and SU-8
5.4 Mask-based UV photopolymerization for mVLSI hydrogel patterning
5.4.1 Lithography setup for the photopolymerization of hydrogels
5.4.2 Hydrogel photopolymerization: experiments and results
5.4.3 Troubleshooting: photopolymerization of hydrogels
5.5 Conclusion: mVLSI technologies for hydrogel-based LoCs
6 Components for chemofluidic circuit design
6.1 Passive components in microfluidics
6.1.1 Microfluidic resistor
6.1.2 Planar-passive microfluidic signal mixer
6.1.3 Phase separation: laminar flow signal splitter
6.1.4 Hydrogel-based microfluidic one-directional valves
6.2 Hydrogel-based active components
6.2.1 Reversible hydrogel-based valves
6.2.2 Hydrogel-based variable resistors
6.2.3 CVPT: the microfluidic transistor
6.3 Conclusion: components for chemofluidic circuits
7 Hydrogel-based logic circuits in planar microfluidics
7.1 Development of a planar CVPT logic concept
7.1.1 Challenges of planar microfluidics
7.1.2 Preparatory work and conceptional basis
7.2 The microfluidic CVPT-RTL concept
7.3 The CVPT-RTL NAND gate
7.3.1 Circuit optimization stabilizing the NAND operating mode
7.3.2 Role of laminar flow for the CVPT-RTL concept
7.3.3 Hydrogel-based components for improved switching reliability
7.4 One design fits all: the NOR, AND and OR gate
7.5 Control measures for cascaded systems
7.6 Application scenarios for the CVPT-RTL concept
7.6.1 Use case: automated cell growth system
7.6.2 Use case: chemofluidic converter
7.7 Conclusion: Hydrogel-based logic circuits
8 Summary and outlook
8.1 Scientific achievements
8.2 Summarized recommendations from this work
Supplementary information
SI.1 Swelling degree of BIS-pNIPAAm gels
SI.2 Simulated ray tracing of UV lithography setup by WinLensÂź
SI.3 Determination of the resolution using the intercept theorem
SI.4 Microfluidic master mold test structures
SI.4.1 Polymer and glass mask comparison
SI.4.2 Resolution Siemens star in DFR
SI.4.3 Resolution Siemens star in SU-8
SI.4.4 Integration test array 300 ÎŒm for DFR and SU-8
SI.4.5 Integration test array 100 ÎŒm for SU-8
SI.4.6 Microfluidic structure for different technology parameters
SI.5 Microfluidic test setups
SI.6 Supplementary information: microfluidic components
SI.6.1 Compensation methods for flow stabilization in microfluidic chips
SI.6.2 Planar-passive microfluidic signal mixer
SI.6.3 Laminar flow signal splitter
SI.6.4 Variable fluidic resistors: flow rate characteristics
SI.6.5 CVPT flow rate characteristics for high Rout
Standard operation proceduresDer Transport von lebenswichtigen NĂ€hrstoffen in FlĂŒssigkeiten sowie der Austausch spezifischer chemischer Signale von Zelle zu Zelle wurde in Milliarden Jahren natĂŒrlicher Evolution optimiert. Dieses Vorbild aus der Natur ist ein treibender Faktor im Fachgebiet der Mikrofluidik, welches die Manipulation kleinster FlĂŒssigkeitsmengen erforscht um diese Effekte in fluidischen Mikrosystemen fĂŒr technische Lösungen zu nutzen. Derzeit finden mikrofluidische Systeme vor allem in der Diagnostik, z.B. wie SARS-CoV-2-Antigentests, oder im Bereich der Hochdurchsatzanalyse, z.B. in der Krebsforschung, besondere Beachtung.
Entweder einfach zu bedienende oder hochintegrierte mikrofluidische Systeme, die biologische und chemische Laboruntersuchungen auf einem sogenannten Lab-on-a-Chip (LoC) durchfĂŒhren, bieten schnelle Analysen, hohe FunktionalitĂ€t, hervorragende Reproduzierbarkeit bei niedrigen Kosten pro Probe und einen geringen Bedarf an Reagenzien durch die Miniaturisierung des Systems. Trotz des groĂen Fortschritts verschiedener LoC-Technologieplattformen in den letzten 30 Jahren mangelt es noch an standardisierten mikrofluidischen Komponenten sowie an einer leistungsstarken, vollintegrierten On-Chip-Automatisierung. Vielversprechend fĂŒr das Design mikrofluidischer Systeme ist die Ăhnlichkeit der Kirchhoff'schen Gesetze aus der Elektronik zur Vorhersage von Druck und Flussrate in Mikrokanalstrukturen. Ein spezifischer Ansatz der LoC-Plattformtechnologie steuert FlĂŒssigkeiten durch aktive Polymere, die auf spezifische physikalische und chemische Signale in der FlĂŒssigkeit reagieren. Analog zur (Mikro-)Elektronik können diese aktiven Polymermaterialien durch verschiedene fotolithografische und mikrostrukturelle Methoden realisiert werden, um funktionelle Elemente mit hoher Skalierbarkeit zu erzeugen.\\
Die sogenannten chemofluidischen Schaltungen haben ein hohes funktionales Potenzial und ermöglichen eine 'wirkliche' on-chip Automatisierung, sind jedoch komplex im Systemdesign. In dieser Arbeit wird ein fortgeschrittenes Schaltungskonzept fĂŒr eine planare mikrofluidische Chiparchitektur vorgestellt, das aus der frĂŒhen Ăra der halbleiterbasierten Resistor-Transistor-Logik (RTL) hervorgeht. Beginnend mit dem Stand der Technik der mikrofluidischen Technologien, werden Materialien und Methoden dieser Arbeit nĂ€her beschrieben. Daraufhin wird die bevorzugte Herstellungstechnologie bewertet und verschiedene mikrofluidische Komponenten werden in Funktion und Design diskutiert. Die wichtigste Komponente, die es zu charakterisieren gilt, ist der auf Hydrogel basierende chemische Volumen-PhasenĂŒbergangstransistor (CVPT), der den SchlĂŒssel zur Realisierung mikrofluidische Logikgatteroperationen darstellt. Dieses Schaltungskonzept (CVPT-RTL) ist robust und einfach im Design und kann mit gĂ€ngigen Materialien und Fertigungstechniken realisiert werden. Zuletzt werden Anwendungsszenarien fĂŒr das CVPT-RTL-Konzept vorgestellt und Empfehlungen fĂŒr die fortlaufende Entwicklung angestellt.:1 The transistor: invention of the 20th century
2 Introduction to fluidic microsystems and the theoretical basics
2.1 Fluidic systems at the microscale
2.2 Overview of microfluidic chip fabrication
2.2.1 Common substrate materials for fluidic microsystems
2.2.2 Structuring polymer substrates for microfluidics
2.2.3 Polymer chip bonding technologies
2.3 Fundamentals and microfluidic transport processes
2.3.1 Fluid dynamics in miniaturized systems
2.3.2 Hagen-Poiseuille law: the fluidic resistance
2.3.3 Electronic and microfluidic circuit model analogy
2.3.4 Limits of the electro-fluidic analogy
2.4 Active components for microfluidic control
2.4.1 Fluid transport by integrated micropumps
2.4.2 Controlling fluids by on-chip microvalves
2.4.3 Hydrogel-based microvalve archetypes
2.5 LoC technologies: lost in translation?
2.6 Microfluidic platforms providing logic operations
2.6.1 Hybrids: MEMS-based logic concepts
2.6.2 Intrinsic logic operators for microfluidic circuits
2.7 Research objective: microfluidic hydrogel-based logic circuits
3 Stimuli-responsive polymers for microfluidics
3.1 Introduction to hydrogels
3.1.1 Application variety of hydrogels
3.1.2 Hydrogel microstructuring methods
3.2 Theory: stimuli-responsive hydrogels
3.3 PNIPAAm: a multi-responsive hydrogel
4 Design, production and characterization methods of hydrogel-based microfluidic
systems
4.1 The semi-automated computer aided design approach for microfluidic systems
4.2 The applied design process
4.3 Fabrication of microfluidic chips
4.3.1 Photoresist master fabrication
4.3.2 Soft lithography for PDMS chip production
4.3.3 Assembling PDMS chips by plasma bonding
4.4 Integration of functional hydrogels in microfluidic chips
4.4.1 Preparation of a monomer solution for hydrogel synthesis
4.4.2 Integration methods
4.5 Effects on hydrogel photopolymerization and the role of integration method
4.5.1 Photopolymerization from monomer solutions: managing the diffusion of free
radicals
4.5.2 Hydrogel adhesion and UV light intensity distribution in the polymerization
chamber
4.5.3 Hydrogel shrinkage behavior of different adhesion types
4.6 Comparison of the integration methods
4.7 Characterization setups for hydrogel actuators and microfluidic measurements . 71
4.7.1 Optical characterization method to describe swelling behavior
4.7.2 Setup of a microfluidic test stand
4.8 Conclusion: design, production and characterization methods
5 VLSI technology for hydrogel-based microfluidics
5.1 Overview of photolithography methods
5.2 Standard UV photolithography system for microfluidic structures
5.3 Self-made UV lithography system suitable for the mVLSI
5.3.1 Lithography setup for the DFR and SU-8 master exposure
5.3.2 Comparison of mask-based UV induced crosslinking for DFR and SU-8
5.4 Mask-based UV photopolymerization for mVLSI hydrogel patterning
5.4.1 Lithography setup for the photopolymerization of hydrogels
5.4.2 Hydrogel photopolymerization: experiments and results
5.4.3 Troubleshooting: photopolymerization of hydrogels
5.5 Conclusion: mVLSI technologies for hydrogel-based LoCs
6 Components for chemofluidic circuit design
6.1 Passive components in microfluidics
6.1.1 Microfluidic resistor
6.1.2 Planar-passive microfluidic signal mixer
6.1.3 Phase separation: laminar flow signal splitter
6.1.4 Hydrogel-based microfluidic one-directional valves
6.2 Hydrogel-based active components
6.2.1 Reversible hydrogel-based valves
6.2.2 Hydrogel-based variable resistors
6.2.3 CVPT: the microfluidic transistor
6.3 Conclusion: components for chemofluidic circuits
7 Hydrogel-based logic circuits in planar microfluidics
7.1 Development of a planar CVPT logic concept
7.1.1 Challenges of planar microfluidics
7.1.2 Preparatory work and conceptional basis
7.2 The microfluidic CVPT-RTL concept
7.3 The CVPT-RTL NAND gate
7.3.1 Circuit optimization stabilizing the NAND operating mode
7.3.2 Role of laminar flow for the CVPT-RTL concept
7.3.3 Hydrogel-based components for improved switching reliability
7.4 One design fits all: the NOR, AND and OR gate
7.5 Control measures for cascaded systems
7.6 Application scenarios for the CVPT-RTL concept
7.6.1 Use case: automated cell growth system
7.6.2 Use case: chemofluidic converter
7.7 Conclusion: Hydrogel-based logic circuits
8 Summary and outlook
8.1 Scientific achievements
8.2 Summarized recommendations from this work
Supplementary information
SI.1 Swelling degree of BIS-pNIPAAm gels
SI.2 Simulated ray tracing of UV lithography setup by WinLensÂź
SI.3 Determination of the resolution using the intercept theorem
SI.4 Microfluidic master mold test structures
SI.4.1 Polymer and glass mask comparison
SI.4.2 Resolution Siemens star in DFR
SI.4.3 Resolution Siemens star in SU-8
SI.4.4 Integration test array 300 ÎŒm for DFR and SU-8
SI.4.5 Integration test array 100 ÎŒm for SU-8
SI.4.6 Microfluidic structure for different technology parameters
SI.5 Microfluidic test setups
SI.6 Supplementary information: microfluidic components
SI.6.1 Compensation methods for flow stabilization in microfluidic chips
SI.6.2 Planar-passive microfluidic signal mixer
SI.6.3 Laminar flow signal splitter
SI.6.4 Variable fluidic resistors: flow rate characteristics
SI.6.5 CVPT flow rate characteristics for high Rout
Standard operation procedure
The evaluation of Corona and Ikonos satellite imagery for archaeological applications in a semi-arid environment
Archaeologists have been aware of the potential of satellite imagery as a tool almost since the first Earth remote sensing satellite. Initially sensors such as Landsat had a ground resolution which was too coarse for thorough archaeological prospection although the imagery was used for geo-archaeological and enviro-archaeological analyses. In the intervening years the spatial and spectral resolution of these sensing devices has improved. In recent years two important occurrences enhanced the archaeological applicability of imagery from satellite platforms: The declassification of high resolution photography by the American and Russian governments and the deregulation of commercial remote sensing systems allowing the collection of sub metre resolution imagery. This thesis aims to evaluate the archaeological application of three potentially important resources; Corona space photography and Ikonos panchromatic and multispectral imager). These resources are evaluated in conjunction with Landsat Thematic Mapper (TM) imagery over a 600 square km study area in the semi-arid environment around Homs, Syria. The archaeological resource in this area is poorly understood, mapped and documented. The images are evaluated for their ability to create thematic layers and to locate archaeological residues in different environmental zones. Further consideration is given to the physical factors that allow archaeological residues to be identified and how satellite imagery and modern technology may impact on Cultural Resource Management. This research demonstrates that modern high resolution and historic satellite imagery can be important tools for archaeologists studying in semi-arid environments. The imagery has allowed a representative range of archaeological features and landscape themes to be identified. The research shows that the use of satellite imagery can have significant impact on the design of the archaeological survey in the middle-east and perhaps in other environments
Application of Osteopathic Manipulative Medicine to Ameliorate Sepsis Induced Ileus
Graduate
Basi
Airborne LiDAR for the detection of archaeological vegetation marks using biomass as a proxy
In arable landscapes, the airborne detection of archaeological features is often reliant on using the properties of the vegetation cover as a proxy for sub-surface features in the soil. Under the right conditions, the formation of vegetation marks allows archaeologists to identify and interpret archaeological features. Using airborne Laser Scanning, based on the principles of Light Detection and Ranging (LiDAR) to detect these marks is challenging, particularly given the difficulties of resolving subtle changes in a low and homogeneous crop with these sensors. In this paper, an experimental approach is adopted to explore how these marks could be detected as variations in canopy biomass using both range and full waveform LiDAR data. Although some detection was achieved using metrics of the full waveform data, it is the novel multi-temporal method of using discrete return data to detect and characterise archaeological vegetation marks that is offered for further consideration. This method was demonstrated to be applicable over a range of capture conditions, including soils deemed as difficult (i.e., clays and other heavy soils), and should increase the certainty of detection when employed in the increasingly multi-sensor approaches to heritage prospection and management
Strange and singlet form factors of the nucleon: Predictions for G0, A4, and HAPPEX-II experiments
We investigate the strange and flavor-singlet electric and magnetic form
factors of the nucleon within the framework of the SU(3) chiral quark-soliton
model. Isospin symmetry is assumed and the symmetry-conserving SU(3)
quantization is employed, rotational and strange quark mass corrections being
included. For the experiments G0, A4, and HAPPEX-II we predict the quantities
and . The dependence
of the results on the parameters of the model and the treatment of the Yukawa
asymptotic behavior of the soliton are investigated.Comment: 16 pages, 3 figures, Final version for publication in Eur. Phys. J.
Poverty and power: Survival of the poorest in three villages of West Bengal, India.
This thesis examines the relation between power and poor people's agency. It does so through critical review of the literature on theories of poverty, and through a comparative analysis of three villages in two contrasting regions of West Bengal, India. Chapters two and three compare two theoretical approaches to poverty. Chapter two notes the connection between the ideology of poverty measurement in nineteenth century Britain and twentieth century India, and discusses mainstream literature on the Indian political economy which concentrates on the poor. The chapter locates a common theme in these two literatures, which are seen to conceptualise the poor as passive and lacking agency. Chapter three considers an alternative theoretical approach, that is literature concerning the dimension of human agency. In particular it analyses the tradition of 'people's history', which conceptualizes the poor as active participants in the making of their societies, as well as contemporary discussion of poor people's participation in rural development. Chapter four gives a background to agrarian West Bengal in terms of history, agro-ecology, agrarian differentiation and politics. Chapter five describes the two study regions, the three study villages, and the methodology used in the field. It also outlines the method of categorization of village households employed in the thesis. The next two chapters present the field work data. Chapter six evaluates the effectiveness of irrigation facilities introduced into the main study village as a means of examining how external resources are mediated through village power structure. The evaluation analyses the relation between irrigation, the local agro-ecology, and power structure. The main benefits of the programme accrued to the village elite, and benefits to the poor were negligible. Chapter seven focusses on poverty as experienced by the poorest, and poorest people's priorities. In contrast to chapter six, it details indigenous efforts at 'development'. It discusses five types of strategies used by sixty purposively selected poorest households that were crucial to their survival: use of common property resources, management of food, sharerearing of livestock, sale of assets, and informal organization into mutual support networks. Poorest people exploited both social and natural resource bases in an attempt to 'negotiate' a better quality of life for themselves within local socio-economic structures. The conclusion stresses the importance of understanding the ways in which the abilities of the poor are conceptualised, and argues that rural development may be more successful if it attempts to understand and build on indigenous strategies already in use by the poor
Are there functional consequences of a reduction in selenium intake in UK subjects?
Dietary Se levels in the UK have fallen over the last 20 years and recent surveys indicate that average Se intakes are 30-40 microg/d, which is well below the current UK reference nutrient intake for adult men (75 microg/d) or women (60 microg/d). Functional consequences of this decline have not been recognised, although epidemiological data suggest it may contribute to increased risk of infections and incidence of some cancers. Previous data have indicated that biochemical changes in Se-dependent proteins occur in otherwise healthy UK subjects given small Se supplements. The current studies have focused on the effect of small Se supplements on the immune response since there is evidence of specific interactions between Se intake and viral replication, and since the potential anti-cancer effects of Se may be mediated by non-antioxidant effects of Se such as changes in immune function. Data indicate that subjects given small Se supplements (50 or 100 microg Se/d) have changes in the activity of Se-dependent enzymes and evidence of improved immune function and clearance of an administered live attenuated virus in the form of poliovirus vaccine. Responses of individual subjects to Se supplements are variable, and current work is evaluating potential explanations for this variability, including genetic variability and pre-existing Se status
Land Administration Domain Model: digitally transforming the land administration ecosystem
The revision of the Land Administration Domain Model (LADM) is significantly changing the scope of the ISO 19152 standard. The focus is shifting from the architectural requirements of the agency, to the architectural requirements of the ecosystem. At the same time, the LADM is recognized as being pivotal to the next phase of digital transformation, where policymakers expect increased operational and process alignment between agencies in the ecosystem. This article summarizes how the LADM can support the digital transformation of the land administration ecosystem
A common variant associated with dyslexia reduces expression of the KIAA0319 gene
This work was supported by the Wellcome Trust (MYD, SP, TSS, JCK, RWM, PC, SB, and APM), the Intramural Research Programs of the National Human Genome Research Institute (MYD and EDG) and National Cancer Institute (MPO), and the NIH/Ox-Cam Graduate Partnership Program (MYD).Numerous genetic association studies have implicated the KIAA0319 gene on human chromosome 6p22 in dyslexia susceptibility. The causative variant(s) remains unknown but may modulate gene expression, given that (1) a dyslexia-associated haplotype has been implicated in the reduced expression of KIAA0319, and (2) the strongest association has been found for the region spanning exon 1 of KIAA0319. Here, we test the hypothesis that variant(s) responsible for reduced KIAA0319 expression resides on the risk haplotype close to the gene's transcription start site. We identified seven single-nucleotide polymorphisms on the risk haplotype immediately upstream of KIAA0319 and determined that three of these are strongly associated with multiple reading-related traits. Using luciferase-expressing constructs containing the KIAA0319 upstream region, we characterized the minimal promoter and additional putative transcriptional regulator regions. This revealed that the minor allele of rs9461045, which shows the strongest association with dyslexia in our sample (max p-value = 0.0001), confers reduced luciferase expression in both neuronal and non-neuronal cell lines. Additionally, we found that the presence of this rs9461045 dyslexia-associated allele creates a nuclear protein-binding site, likely for the transcriptional silencer OCT-1. Knocking down OCT-1 expression in the neuronal cell line SHSY5Y using an siRNA restores KIAA0319 expression from the risk haplotype to nearly that seen from the non-risk haplotype. Our study thus pinpoints a common variant as altering the function of a dyslexia candidate gene and provides an illustrative example of the strategic approach needed to dissect the molecular basis of complex genetic traits.PostprintPeer reviewe
Participatory politics, environmental journalism and newspaper campaigns
This is an Author's Accepted Manuscript of an article published in Journalism Studies, 13(2), 210 - 225, 2012, copyright Taylor & Francis, available online at: http://www.tandfonline.com/10.1080/1461670X.2011.646398.This article explores the extent to which approaches to participatory politics might offer a more useful alternative to understanding the role of environmental journalism in a society where the old certainties have collapsed, only to be replaced by acute uncertainty. This uncertainty not only generates acute public anxiety about risks, it has also undermined confidence in the validity of long-standing premises about the ideal role of the media in society and journalistic professionalism. The consequence, this article argues, is that aspirations of objective reportage are outdated and ill-equipped to deal with many of the new risk stories environmental journalism covers. It is not a redrawing of boundaries that is needed but a wholesale relocation of our frameworks into approaches better suited to the socio-political conditions and uncertainties of late modernity. The exploration of participatory approaches is an attempt to suggest one way this might be done
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